Due to increasing popularity and significant technological developments in the field of additive manufacturing, it has become critical to develop an efficient, sterile, and disposable chamber for 3D printing. As physicians, manufacturing professionals, and individuals make more common use of 3D printing systems, there will be a need to print many different types of materials, including tissue, in a sterile chamber which can simply and rapidly be exchanged to allow for printing of diverse materials. An article in New York Times, Jan. 27, 2015 entitled “The Operation Before the Operation”, p. D6, describes a need for anatomical models for medicine and the use of 3D printed models.
The need for making anatomical models and actual body parts by additive manufacturing was realized many years ago. The state of the art in this field several years ago was summarized in an article entitled “Rapid prototyping techniques for anatomical modeling in medicine” by M. McGurk et al. in Ann. R. Coll. Surg. Engl. 1997; 79; 169-174 wherein 3-D printing of models was described. Models were created by spraying liquid through ink jet printer nozzles on a layer of precursor powder, creating a solid thin slice. The printing process was repeated for each subsequent slice until the object was completed as a “green-state” part that was then fired in a furnace to sinter it. The resulting object was then further treated to make a full density part.
In recent years the development of software for computer controlled robotic X-Y motion systems used in the semiconductor and optics industries has made 3D printing of large objects easier than in former years. Software programs such as SolidWorks, AutoCad 360, and similar software programs make layered construction of 3D objects a relatively low cost and fast task for 3D printing equipment.
To achieve 3D printing of larger objects, print nozzles are directed in the X-Y plane either by placing the object to be made on an X-Y table wherein motion is provided below the nozzles, or mounting rails above the nozzles for X-Y motion directed from above the nozzles. An example of an X-Y table for motion below the nozzles is shown in U.S. Pat. No. 5,760,500 to T. Kondo et al. wherein linear actuators or stepper motors provide independent motion to a table over the X-Y plane. Highly accurate stepper motors for this purpose are described in U.S. Pat. No. 7,518,270 to R. Badgerow and T. Lin. A 3-D printer with overhead control of nozzles is described in U.S. Pat. No. 5,740,051 to R. Sanders et al.
In either motion situation, the nozzles move in the X-Y plane relative to the printed object and also move up in the Z plane starting from a lower level and proceeding upwardly. A layer or lamella is first printed at a low level and then the next layer up is printed and so on until the model or object is completed. Sometimes two nozzles are used, including a first nozzle to spray or extrude a manufacturing material, such as a polymer, and a second nozzle to spray a support fluid for the manufacturing material, which may be soft or viscous. An example of a support fluid may be an ink jet sprayed, ultra violet light cured resin. When the manufacturing material hardens, the faster drying support fluid is dissolved out. The use of chamber or accordion pleated sleeves in glovebox environments is known from U.S. Pat. No. 3,456,812 to J. Gandolfo et al.
Currently, many researchers, industry professionals, and individuals are looking to additive manufacturing by 3D printing as the future of custom manufacturing of everything from organs to food products. Additive manufacturing provides the flexibility to produce diverse items very rapidly and at much lower cost than many previous manufacturing methodologies. In particular, additive manufacturing technology by 3D printing techniques for patient-specific and potentially patient-derived tissue and bone using tissue and stem cells. An object of the invention was to develop a sterile manufacturing environment compatible for 3D printing equipment that could be used for biological object manufacturing, as well as the validation of effective post-manufacturing sterilization of the manufacturing equipment.